For proper monitoring, you’ll need to properly position the sensor on the patient’s head and verify the acquired signal.
Step 1 - trigger monitoring session
From the main screen click on new session (1) button to start monitoring session.
TIP - For login instructions and pairing sensor please read section 6.3 loging into app and pairing sensor.
Step 2 - fill in patient data
At the beginning of the monitoring session, an optional step is to fill patient data. This information will be used and recorded in the final report. Fill in all data correctly and click on “start monitoring”(1) as shown in Figure 6.5-2
TIP - For faster monitoring, you can choose to skip this step, but for the report to be generated, you will have to fill in the patient information at the end of the monitoring session.
When starting a monitoring session the app will show a screen to help with sensor positioning. This will inform you about the headband tightness. Before placing the sensor on the patient's head the option will show that the sensor is too loose (Figure 6.5-3).
Step 3 - position the sensor
With the sensor and headband assembled, place them around the patient's head as shown in Figure 6.5-4
The sensor should contact the scalp in the temporoparietal region about 2 inches (5-6 cm) above the entrance of the external acoustic meatus in the coronal plane and just below the head protrusion where the circumference is greatest. This is position (B ) in Figure 6.5-5. Both sides of the head will work for sensor placement.
Position (A) in Figure 6.5-5 is another good option. The sensor must be positioned in the region of the temples (mid eyebrow line), i.e., at 15% of the reference point Fpz towards the Oz reference points at the back of the head following the circumference of the skull.
Once the sensor is placed, tighten the turnbuckle into a snug, comfortable fit, turning it clockwise until a final click can be heard without excessive force. A proper adjustment will result in a green OK! on the app screen (Figure 6.5-7)
If the patient is awake, ask if he is comfortable with the pressure. If not, readjust the headband for a comfortable fit.
In conditions where patients are unresponsive, check for signs of discomfort or skin damage for at least every five minutes.
Excessive tightening will be indicated with a “sensor too tight” message (Figure 6.5-6). In such a case loosen the turnbuckle until the green message of OK! appears (Figure 6.5-7).
ATTENTION - If TOO LOOSE (Figure 6.5-3) or TOO TIGHT (Figure 6.5-6) is being shown the start monitoring button will be inactive. Adjust the turnbuckle until the positioning bar turns green with OK! and then button will be active.
PRECAUTION - The patient position or movement and the BcSs-PICNIW-1000 sensor is known to affect the signal being recorded. As a result, if multiple recording sessions are obtained on the same patient, consistent positioning of the patient and device will lead to more comparable recordings.
PRECAUTION - Do not press the sensor pin with hand or any other object, this may damage the sensor.
Step 4a - assisted signal quality check (option with internet)
ATTENTION - this assisted verification option will only appear if there is an internet connection.
When the sensor tightness is adequate, the B4C System will start collecting a 30 second sample of the captured signal (Figure 6.5-7). This sample be processed to verify if there is a technical problem in the signal quality.
An average 30 second pulse will be presented with respective confidence intervals (Figure 6.5-8). This sample will be updated every 5 seconds. The intent of this sample is to facilitate the operator's visual signal quality check.
In some situations, the signal being captured by the sensor will not have sufficient technical quality. The system will indicate the excessive noise, meaning there is a need to stabilize the patient and/or adjust the sensor (Figure 6.5-9).
ATTENTION - The signal quality check is NOT a clinical check. The is a technical check and the noise message (insufficient signal quality) will be displayed when one or more of the four conditions below are true:
The signal-to-noise ratio is not satisfactory (signal with lack of physiological characteristics)
The amount of artifacts is excessive (too much movement being captured in the signal)
The processed signal will result in a statistically non-significant P2/P1 ratio
Processed signal will result in a non-physiological Time-to-Peak range
If the sensor is positioned correctly, the waveform shown on the positioning screen should have a typical ICP waveform characteristic. The familiarity with the waveform is a healthcare professional interpretation based on their experience and exposure to ICP waveforms.
Step 4b - unassisted signal quality check (option w/o internet)
When the sensor tightness is adequate and there is no internet connection, the sensor positioning bar will turn green. In this case, a visual check of the signal quality is suggested before starting a monitoring session.
Only adequate tightening does not guarantee that the signal is of satisfactory quality. The position of the sensor on the head also influences the signal quality. If required, loosen the headband by turning the turnbuckle counterclockwise and try to reposition the sensor and/or varying the tightness until a familiar ICP waveform signal appears.